Support for vibration translating devices



P 1936. H. c. HARRISON ET AL I 2,038,216

SUPPORT FOR VIBRATION TRANSLATING DEVICES Filed Dec. 29, 1954 2Sheets-Sheet 1 FIG.

' Y .-H.C. HARRISON WVENTORS' AC. KELLER A TTORNEV April 1936. H. c.HARRISON ET AL 2,033,213

SUPPORT FOR VIBRATION TRANSLATING DEVICES Filed Dec. 29, 1354 2Sheets-Sheet 2' FIG. 5

: zgg ogs; v '1 c; KELLER ATTORNEY Rt; HARRISON W a flange parallel tothe record and means for sup- Patented Apr. 21, i936 UNITED STAT Thisinvention surroa'r Foa PATE VIBRATION 'raArisLaTmG DEVICES Henry C.Harrison. Port Washington, and Arthur 0. Keller, Mount Vernon, N. Y.,as'aignors to Bell Telephone Laboratories,

Incorporated, v

New York. N. Y., a corporation of' New York 1 Application relates tosound recordingand reproducing systems and the ,object of the inventionis an impr translating devices such as recorders or repro ducers.

In a copending oved; structure for supporting application of A. C.Keller and I I. S. Refuse, Serial No. 731,428; filed June 20, 1934, nowPatent No. 1,990,548, thereis disclosed asystem for supportingthesedevices in operative relation to a record member whichcompriseszessentially a fluid conduit on the device terminating inplying to the conduit a fluid, such as compressed air, which flowsradially outward between the flange and the record surface and setsupa'. balanced system of forces for maintaining the stylus of the deviceat the proper level with respect to the record surface.

In the suppor "the fluid conduit ting system of this invention 'issecured to an arm eccentrically'pivoted atone side of the device andhaving two identical orifices for receiving the flange, one on each sideof the stylus. The flange is closed by i a suita attached to one of theorifices and the other is ble-plug, the choice of orifices for theflange depending on whether the device is to move radially inward orradially outward on the record.

The arm is preferably spring These and other features of the inventionwill be more clearly understood from the following detailed descriptionin the accompanying drawings, in which:

Fig. 1 is a side view of a disc recorder equipped with an improved theinvention;

Fig. 2 is a bottom air advance ball according to view of the recorder;

-'Fig. 3 is a mechanical advance ball which ca be used with therecorder;

. Fig; 4 is a detail trap for deflecting- .view of the flange and thethe air from the stylus;

Fig. 5 is a perspective view of the air advance mechanism;

'Fig. dis-an. ex ball mechanism.

and ploded view' of the air advance having a threaded hole l9 above theopening 44 about its pivot and against which the arm is held tion of therecording surface. This condition'is Y is turned so that the segment 38lies between December 29, 1934, Serial No.- 159,682 I 6 Claims. (01.274-1) The translating device ii shown for purposes. of illustration isa recorderof a'well-known elect-romegnetictype mounted on a horizontalpivot -'l2 with the cutting stylus l3 in position on the recordingsurface It. The arm I 5 is pivotally mounted by the screw it on a plateI! secured to the side of the recorder housing and has a projection" l8extending-laterally through the opening 41 in the' housing around thestylus and in the housing for receiving the flange -or the plug 21. Asimilar threadedhole 22 is provided in the bottom of the. arm and an airpath 23 connects the holes is and 22 with the tube-24 on the upper sideof the arm.

This tube is connected to a suitable source 25 of compressed air througha pressure reducing valve 26 by a flexible tube 21. The arm I5 is fittedwith a plug 28 having an eccentric hole 29 for the screw l6 and, aprojecting handle 30 20 for rotating, the plug to provide verticaladjustment in the pivot mounting of the arm. At

the front of therecorder, the plate is fitted with an adjusting screw 8|for rotating the arm by the tension of the spring 32. I Better resultscan usually be obtained with the air advance ball by mounting the'flangeso that it moves ahead of the stylus across the uncut porreadilyobtained with this invention for recorder movement in either directionsince the flange 20 and the plug 2' are interchangeable. In order toprevent the air escaping between the flange and the record surface from.producing a modulating eifect on thevlbrations of the stylus, an

improved adjustable air trap is provided. As

shown more clearly. in Figs. 2 and 4, the disc 33, which flts' looselyover the threaded tubular portion 34 of the flange 20, has a boss 35which engages the arm I! and a segment 36 projecting downwardly to theplane of the face of the flange to" form a groove 31. 'In connecting theflange to the arm in either position the disc 33 the flange and thestylus. The groove 31 provides a path of low impedance as compared withthe path between the recording surface and the segment 38 and. thegreater part of the air flowing toward the stylus is therefore deflectedby thesegment and escapes through the ends of the groove.

When using a mechanical advance ball it is not always necessary toadjust the axis of the replane of the recording surface'but with the airadvance ball the face of the flange should be po-.

sitioned with considerable .care. This is conveniently accomplished withthe flange in either position by means of the rotatable plug 28 and thescrew 3 ldescribed above.

The air supplied to the tube 24 at a suitable pressure (within the rangeof about 5 to 15' pounds gauge pressure) passes through the ann I! tothe flange 20 and radially outward between the flange and the recordingsurface. As'explained more fully in the application referred to.

above,-this radial flow of air sets up a balanced system of forces sothatthe recorder is supported in stable equilibrium with the flange afew mils above the recording surface. In order to prevent anobjectionable rush of air and excessive noise when the recorder is beingplaced on the record or lifted therefrom while the valve 26 is open,there is provided between the valve and the flange and preferably in thetube 24 a flow restricting device 38. This may take the form of affiiug,one-half inch to one inch in lengthwith a hole '39 of materially smallerbore than the tube. The

dimensions of the plug are not critical but it should have sufllcientimpedance to limit the "free flow of air to a satisfactory degree butshould pass enough air for normal operating purposes.

For example, when using the conventional rewhen compressed air is notavailable or if for some other reason it' is desirable to use amechanical advance ball, this may be done without change-in the recorderstructure by providing a member 40 in which amecha'nical advance ball(the case requires.

4| is fitted as shown in 'Fig. 3. The screw 42 fits either of the holesI! or 22 so that the ball 4| can be secured in either operating positionas Whilethe invention has been described with reference to its use witha particular recorder it will be understood that it is equally.applicable to reproducers or other devices to be supported in accuraterelationship to moving surfaces.

7 9,088,218 corder to accurate parallel relationship to the What isclaimed is:

1. The combination with a record, a vibration translating devicecooperating therewith, a fluid conduit on the device having a flange inclose spaced relation to the record and means for producing a flow offluid between the flange and the record for maintaining the spacebetween them, of a section of restricted area in the conduit forlimiting the flow of fluid when the device is lifted from the record.

2. The combination with a record, a vibration translating .devicecooperating therewith, a fluid conduit on the device having a flange inclose spaced relation to the record and means for producing a flow offluid between the flange and the record for maintaining the spacebetween them,

of a support for the conduit and an eccentric pivot for the support foradjusting the face of the flange into parallel relationship with thesurface of the record.

3. The combination with a record, a vibration translating device havinga stylus cooperating therewith and a flange, of means for mounting theflange in close spaced relation to the record on either side of thestylus, and means for produclng a flow of fluid radially of the flangein either position.

4. The combination according to claim 3 in which the flange is threadedinto the conduit and is provided with an air trap along a portion of itsperiphery, the .trap being rotat'ably adjustable with respect to theflange.

5. The combination according to claim 3 in which the flange mountingmeans is secured to the device byan eccentric pivot for adjusting theflange into parallel relationship to the record.

6. The combination with a record, a vibration translating devicehaving-a stylus cooperating therewith, a flange and means for producinga flow of fluidradially of the flange to support the device, of meansfor mounting the flange on the device comprising an arm pivotallymounted on one side of the stylus and having a fluidconduit extending tothe other side of the stylus, means for attaching the flange to theconduit at either side of the stylus, means for rotating the' arm on itspivot mounting, and means for vertically adjusting the pivot.

HENRY C. HARRISON. ARTHUR C. KEILER.

